This training program consists of pre- and post-doctoral training in Cancer Epidemiology, Biostatistics, and Environmental Health Sciences. The Epidemiology component focusses on the acquisition of the knowledge necessary to formulate meaningful hypotheses and to design, carry out, analyze, and interpret epidemiologic studies concerned with cancer etiology and prevention. The Biostatistics component emphasizes the development and application of statistical methods for use in studies of survival, etiology, prevention, and risk assessment. The Environmental Health Sciences component has a dual emphasis: the design and conduct of biochemical and molecular epidemiologic studies, and the development and application of laboratory methods for assaying human samples. All the trainees are expected to develop a broad-based appreciation of cancer research, ranging from epidemiology, molecular genetics, cell biology, pathology and carcinogenesis, to clinical oncology, the natural history of the disease and its therapy. At the pre-doctoral level, the program emphasizes the development of expertise in epidemiologic methodology and substantive knowledge through the coursework, seminars, and research experience expected of all pre-doctoral students, and to focussed research in cancer epidemiology, biostatistics and environmental sciences. Six positions for predoctoral trainees are requested. At the post-doctoral level the emphasis is on supervised research and seminars in the three participating areas of cancer-related public health, with formal courses included when desirable. Six post-doctoral positions are requested. Academic training is given primarily at the School of Public Health and in other departments of the Faculty of Medicine. Opportunities for research for all the trainees are available in the participating divisions, with a large number of funded projects available from which to choose. Laboratory facilities are available in the Columbia- Presbyterian Cancer Center and the Division of Environmental Health Sciences. All trainees are expected to take certain courses. A seminar series is held bimonthly, attended by all the trainees and faculty, at which each trainee is expected to present twice each year, facilitating interaction among the trainees and faculty and providing an opportunity for training in public speaking.